1. Field of the Invention
The present invention relates to a liquid droplet ejecting head, an image recording apparatus, a recording method, and an image recording method, and in particular, to a liquid droplet ejecting head, image recording apparatus, recording method and image recording method equipped with a driving element which causes a liquid droplet to be ejected from a corresponding nozzle by being driven in accordance with a driving waveform supplied thereto.
2. Description of the Related Art
As conventional image recording apparatuses, there are known image recording apparatuses such as inkjet recording apparatuses and the like which record dots corresponding to respective pixels of image data by ejecting liquid droplets of ink or the like from plural nozzles.
In such an image recording apparatus, the displacement of a driving element, which arises due to a driving waveform, which is for timewise driving a driving element such as a piezo element or the like in accordance with the amount of an ink droplet, being supplied to the driving element, is transferred via a vibrating plate to a pressure chamber filled with ink. An ink droplet is thereby ejected from the nozzle due to the fluctuations in pressure within the pressure chamber. By using such a piezo method, an ink droplet which corresponds to image data is ejected from a nozzle such that a dot is recorded.
In order to obtain good image quality, good ink eject at all of the nozzles is desirable. However, in actuality, from the standpoints of machining accuracy and costs, it is difficult to carry out good ink eject at all of the nozzles, and there are cases in which dispersion arises in the amounts of ink ejected from the respective nozzles. Further, when the characteristics of the ink vary due to changes in the environment such as the temperature and the humidity or the like, even if the same driving waveform is supplied to the driving elements, dispersion may arise in the amounts of the ink droplets which are ejected.
In order to correct such dispersion in the amounts of ink droplets which are expelled, there is known a method of correcting the driving waveform in accordance with the environmental changes and the characteristics of the nozzles (see, for example, Japanese Patent Application Laid-Open (JP-A) No. 7-241992).
In the technique disclosed in JP-A No. 7-241992, plural heat pulses and plural pre-heat pulses are supplied as a driving waveform to a base for a recording head. At this time, the plural heat pulses and the plural pre-heat pulses are supplied, by dedicated signal lines respectively, to the base via plural corresponding input terminals provided at the substrate. At the base for the inkjet recording head, one of the heat pulses and one of the pre-heat pulses are selected from among the supplied plural heat pulses and plural pre-heat pulses, and are supplied to the corresponding driving element. By applying this technique, the dispersion in the ink droplet amounts can be corrected if a driving waveform corresponding to the environmental temperature and humidity is supplied to the base for the recording head.
However, in the above-described technique, in order to supply each of plural driving waveforms to the liquid droplet ejecting head which serves as the recording head, a number of dedicated signal lines, which number corresponds to the number of driving waveforms, must be provided, and there are the problems that the structure becomes complex, and the liquid droplet ejecting head and the image recording apparatus become large. Further, in recent years, liquid droplet ejecting heads have become known which are structured such that a liquid droplet ejecting head, in which plural driving elements are lined-up in a row, is considered as one unit, and plural these unit liquid droplet ejecting heads are lined-up. In such a technique, there is the concern that the increase in the number of signal wires in particular will become problematic.
A method of serially supplying plural driving waveforms to the liquid droplet ejecting head by one signal wire has been thought of. However, because image recording apparatuses are becoming more high-speed, there are cases in which the time for supplying the driving waveforms becomes problematic.